$ration : 750 / 15;
@function px2rem($px){
  @return $px / $ration + rem;
}

@mixin center{
  display: flex;
  justify-content: center;
  align-items: center;
}
@mixin left{
  display: flex;
  justify-content: flex-start;
  align-items: center;
}
@mixin right{
  display: flex;
  justify-content: flex-end;
  align-items: center;
}
